The foundation for healthy permanent teeth in children and teenagers is laid during the first years of life. Poor diet, poor habits of food intake and inadequate toothbrushing habits during the first 2 years of life have been shown in several studies to be related to tooth decay in children. The development of caries in primary teeth further increases the risk of developing caries in permanent teeth.
Therefore it is essential to establish a proper oral hygiene routine early in life to help ensure the development of strong and healthy teeth. Parents, as consistent role models, are key for setting a daily routine and to making their children understand the importance of oral hygiene. Toothbrushing should be presented as a habit and an integral part of the daily hygiene routine. Children are very sensitive to social stimuli such as praise and affection, and learn best by imitating their parents. Physiological and mental development affects the oral care of children.
Importance of the primary dentition
Primary teeth start to erupt in children from the age of six months. The primary dentition is complete by approximately two and a half years of age. The enamel of primary teeth is less densely mineralised than the enamel of permanent teeth, making them particularly susceptible to caries. Primary teeth are essential tools, both for chewing and learning to talk. They help to break up food into small pieces, thereby ensuring efficient digestion. A full set of teeth is an essential prerequisite in learning correct pronunciation. Primary teeth also play a vital role in the proper alignment and spacing of permanent teeth; it is therefore imperative that they are well cared for and preserved until normal ex-foliation takes place. Establishing a proper oral care routine early on in life sets the foundation for the development of healthy and strong permanent teeth. In addition to good oral hygiene, diet also plays a key role in keeping teeth healthy. In this respect it is not only the quantity of sugar that is important, but also the frequency of consumption. As much as possible, children should be limited in the amount of sweets between meals, especially in the evening or at night.
New permanent teeth
Although permanent teeth are already partly formed in children aged 0 to 3 years, eruption only occurs later in life (from about 6 years on) when the 32 permanent teeth (16 in the upper and 16 in the lower jaw) replace the 20 primary teeth. During this time root resorption and crown shedding of primary teeth takes place. With the eruption of the first permanent teeth (from about 6 years on), the mouth contains a mixture of both primary and permanent teeth, which puts children at increased risk of caries. Often the eruption of the first permanent tooth is not realised by either the child or the parents, because it is positioned behind the last primary molar and is not replacing any primary tooth. Although enamel is fully formed at eruption the surface remains porous and is inadequately mineralised. Subsequently, a secondary mineralisation occurs (second maturation), in which ions from the oral cavity penetrate hydroxyapatite and increase the resistance of the enamel against caries. Furthermore, any primary teeth with caries form reservoirs of bacteria, which can easily attack the immature enamel of the new permanent teeth. During the eruption, the occlusal surfaces of the new permanent teeth are on a lower level than the primary teeth. Toothbrushing becomes more difficult than before, given the coexistence of loose primary teeth, gaps and newly erupting permanent teeth. The jaw is also growing significantly, making space for more teeth. The cleaning of the narrower interdental spaces becomes more important with increasing numbers of permanent teeth.
Role of Parents
Parents have a key role in helping their children to develop a proper oral hygiene routine in the first years of their life. Parents should lead and supervise their children’s toothbrushing approximately for the first 12 years, until motor and mental functions allow the child to routinely perform a proper toothbrushing technique alone. After brushing the teeth for their children for the first 2 years of life, parents will have to use playful motivation to encourage their children to brush their own teeth from about 3 years onwards – the time when children want to brush their teeth alone. Each time the child has finished brushing, parents should re-brush the hard-to-clean areas. At the age of around 6 years, children are able to brush their teeth using a proper brushing technique. In this phase, parents have to continue supervising the regular brushing efforts of their children. The special anatomical situation of changing dentition makes it indispensable that parents still need to help their children in the daily toothbrushing task until eruption of the second molar (around the age of 12).